At the present time, automatic tire mounting equipment is often used for the industrial or commercial mounting of tires on wheel rims or disk wheels for vehicles. It is known to make the tire mounting apparatuses adjustable so that various different wheel rim or disk types and sizes can be accommodated, i.e. can have tires mounted thereon in succession one after another. In that regard, different types or sizes of tires with different profile ratios of about 65% to 25% are mounted on such different wheel rim types. For that purpose, an adjusting arrangement may be provided on the tire mounting head of the tire mounting apparatus, with which the tire mounting tools of the tire mounting head can be automatically adjusted to different wheel rim or disc types with different widths and diameters. Particular difficulties in this automatic adjustment are caused by the large range of different wheel rim or disk diameters from 12 inches to 25 inches for present typical wheel rims. While carrying out this adjustment to accommodate such a large range of wheel sizes, the tire mounting tools must be radially adjusted in different radial directions to achieve the appropriate tool positions relative to the wheel for all possible wheel sizes.
A tire mounting apparatus of the above mentioned type with an automatic adjusting arrangement is known from the German Patent DE 102 22 164 C1. This tire mounting apparatus comprises a wheel rim holding or clamping arrangement on which a provided wheel rim or disk is supported and clampingly held in a horizontal orientation. A rotatably driven mounting head is arranged above the wheel rim or disk. Tire mounting tools including a tire bead deflector, a tire sidewall pressing roller, and a tire sidewall hold-down member are secured on the mounting head. In that regard, the bead deflector and the pressing roller are arranged at a small spacing distance from one another on a common horizontal support arm, by which the tools are positionable on two different circular paths about the rotation axis or wheel axis, and are individually adjustable in the axial or vertical direction by two spindle drives. The support arm in its entirety is adjustable in common to certain radii about the wheel axis by a separate radial spindle drive, so that the mounting apparatus can be adjusted to permit it to automatically mount, in succession after one another, different tires with different diameters and profile ratios onto wheel rims or disks with different widths and wheel diameters.
In that known apparatus, because the bead deflector and the pressing roller are horizontally rigidly connected with one another by the support arm, the bead deflector finger and the pressing roller that rolls or runs tangentially along the tire sidewall are essentially only exactly adjustable to a single predetermined tire and rim size, due to the changing tangential angles of these mounting tools that vary along with the varying working position diameter. In other words, as the mounting tools are adjusted to a different working diameter, the tangential angle setting of the tools relative to the circumferential path around the tire sidewall changes. Namely, at large deviations from the tire or wheel rim size that is predetermined for an exact tangential positioning, e.g. for very large or very small wheel sizes deviating from the nominal or average size, the pressing roller will no longer lie exactly tangentially on the tire sidewall and/or the bead deflector shoe will be positioned with a disadvantageous angular position relative to the inner wall of the tire bead or to the outer edge of the wheel rim flange. This can lead to problems in the tire mounting operation, or can lead to damage of the tire sidewall or bead edge, especially at the extreme ends of large adjustment ranges or when mounting extremely low profile tires. Thus, such a tire mounting machine can only be used for mounting a limited range of different tire and wheel rim sizes. Present typical wheels for passenger automobiles are provided in a wheel rim or disk diameter range from 12 inches to 25 inches, which is too large a range to be accommodated by the known conventional tire mounting machines. Namely, with such a tire mounting machine, it is not possible to successively mount tires covering the entire tire size spectrum without problems and without carrying out manual adjustments for switching tire sizes.